Trials@uspto.gov
`571-272-7822
`
`Paper 14
`Date: October 20, 2021
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`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`UNIFIED PATENTS, LLC,
`Petitioner,
`
`v.
`
`ELECTRONICS AND TELECOMMUNICATIONS
`RESEARCH INSTITUTE,
`Patent Owner.
`
`IPR2021-00827
`Patent 9,781,448 B2
`
`
`Before JAMESON LEE, SALLY C. MEDLEY, and
`NATHAN A. ENGELS, Administrative Patent Judges.
`
`LEE, Administrative Patent Judge.
`
`DECISION
`Denying Institution of Inter Partes Review
`35 U.S.C. § 314
`
`
`
`
`
`
`

`

`IPR2021-00827
`Patent 9,781,448 B2
`
`A.
`
`INTRODUCTION
`I.
`Background and Summary
`On April 22, 2021, Unified Patents, LLC (“Petitioner”) filed a petition
`(Paper 1, “Petition”) requesting inter partes review of claims 1 and 3
`(“challenged claims”) of U.S. Patent 9,781,448 B2 (Ex. 1001, “the ’448
`patent”). Electronics and Telecommunications Research Institute (“Patent
`Owner”) filed a preliminary response. Paper 7 (“Prelim. Resp.”). Petitioner
`filed an authorized reply. Paper 11 (“Prelim. Reply”). Patent Owner filed
`an authorized sur-reply. Paper 12 (“Prelim. Sur-Reply”).
`An inter partes review may not be instituted unless “the information
`presented in the petition . . . and any response . . . shows that there is a
`reasonable likelihood that the petitioner would prevail with respect to at least
`1 of the claims challenged in the petition.” 35 U.S.C. § 314(a). Further, a
`decision to institute may not institute on fewer than all claims challenged in
`the petition. SAS Inst., Inc. v. Iancu, 138 S. Ct. 1348, 1359–60 (2018). We
`determine that Petitioner has not shown a reasonable likelihood of prevailing
`on any claim.
`Accordingly, the Petition is denied, and no inter partes review is
`instituted.
`
`B.
`
`Real Parties-in-Interest
`Petitioner identifies only itself as real party-in-interest. Pet. 1, 1.
`Patent Owner identifies itself, Dolby Laboratories, Inc., Dolby Laboratories
`Licensing Corporation, and Access Advance LLC as real parties-in-interest.
`Paper 4, 2.
`Patent Owner contends that the Petition fails to name all real parties-
`in-interest (“RPIs”) as required by 35 U.S.C. § 312(a)(2). Prelim. Resp. 72–
`
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`IPR2021-00827
`Patent 9,781,448 B2
`78. Patent Owner contends that Petitioner also should have named
`Petitioner’s SEP Video Codec Zone members as RPIs. Id. Because we
`determine Petitioner has not demonstrated a reasonable likelihood of
`prevailing in establishing the unpatentability of any challenged claim, we do
`not reach this issue.
`
`C.
`
`Related Matters
`Neither party identifies any related district court litigation or any
`Board proceeding involving the ’448 patent. Paper 1, 1; Paper 4, 2.
`
`D.
`
`The ’448 patent
`The ’448 patent is directed to a method and apparatus for performing
`intra-prediction by applying an adaptive filter to surrounding pixel values of
`a block to be intra-predicted or the predicted pixel values of a current block.
`Ex. 1001, 1:65–2:2. The ’448 patent states:
`[T]here is provided a method of performing intra-prediction. The
`method of performing intra-prediction includes determining
`whether to apply a first filter to a reference pixel value based on
`information about surrounding blocks of a current block, if, as a
`result of the determination, the first filter is determined to be
`applied, applying the first filter to the reference pixel values,
`performing intra-prediction for the current block based on the
`reference pixel value, determining whether to apply a second
`filter to a prediction value for each prediction mode of the current
`block, predicted by performing the intra-prediction based on the
`information about the surrounding blocks, and if, as a result of
`the determination, the second filter is determined to be applied,
`applying the second filter to the prediction values for each
`prediction mode.
`Id. at 2:11–26. The method is not limited to application in an encoder or a
`decoder. The ’448 patent further states:
`
`In another aspect, there is provided an encoder. The
`encoder includes a processor and memory connected to the
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`IPR2021-00827
`Patent 9,781,448 B2
`processor and configured to store pieces of information for
`driving the processor. The processor is configured to determine
`whether to apply a first filter to a reference pixel value based on
`information about surrounding blocks of a current block, if, as a
`result of the determination, the first filter is determined to be
`applied, apply the first filter to the reference pixel value, perform
`intra-prediction for the current block based on the reference pixel
`value, determine whether to apply a second filter to a prediction
`value for each prediction mode of the current block, predicted by
`performing the intra-prediction based on the information about
`the surrounding blocks, and if, as a result of the determination,
`the second filter is determined to be applied, apply the second
`filter to the prediction value for each prediction mode.
`Id. at 2:54–3:3.
`
`The ’448 patent still further states:
`In yet another aspect, there is provided a decoder. The
`decoder includes a processor and memory connected to the
`processor and configured to store pieces of information for
`driving the processor. The processor is configured to determine
`whether to apply a first filter to a reference pixel value based on
`information about surrounding blocks of a current block, if, as a
`result of the determination, the first filter is determined to be
`applied, apply the first filter to the reference pixel value, perform
`intra-prediction for the current block based on the reference pixel
`value, determine whether to apply a second filter to a prediction
`value for each prediction mode of the current block, predicted by
`performing the intra-prediction based on the information about
`the surrounding blocks, and if, as a result of the determination,
`the second filter is determined to be applied, apply the second
`filter to the prediction value for each prediction mode.
`Id. at 3:4–3:20.
`Claims 1 and 3 are each independent and reproduced below:
`1.
`A video decoding apparatus, comprising:
`a processor to determine whether to apply a first filter to a
`reference pixel value of a current block based on at least one
`of an intra prediction mode of the current block and a size of
`the current block,
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`IPR2021-00827
`Patent 9,781,448 B2
`apply the first filter to the reference pixel value if, as a result of
`the determination, the first filter is determined to be applied,
`and,
`perform intra-prediction for the current block based on the
`reference pixel value,
`wherein when the first filter is determined to be applied,
`the processor calculates a difference value using the
`reference pixel values, compares
`the calculated
`difference value with a specific threshold and applies
`the first filter to the reference pixel value based on
`comparison of the specific threshold and the calculated
`difference,
`when the intra-prediction for the current block is
`performed, the processor determines whether to apply
`a second filter to a prediction value of the current block
`based on at least one of the intra prediction mode of the
`current block and the size of the current block, and
`applies the second filter to the prediction value of the
`current block if, as a result of the determination, the
`second filter is determined to be applied.
`Ex. 1001, 12:2–25.
`3.
`A video encoding apparatus, comprising:
`a processor to determine whether to apply a first filter to a
`reference pixel value of a current block based on at least one
`of an intra prediction mode of the current block and a size of
`the current block,
`apply the first filter to the reference pixel value if, as a result of
`the determination, the first filter is determined to be applied,
`and,
`perform intra-prediction for the current block based on the
`reference pixel value,
`wherein when the first filter is determined to be applied,
`the processor calculates a difference value using the
`reference pixel values, compares
`the calculated
`difference value with a specific threshold and applies
`the first filter to the reference pixel value based on
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`IPR2021-00827
`Patent 9,781,448 B2
`comparison of the specific threshold and the calculated
`difference,
`when the intra-prediction for the current block is
`performed, the processor determines whether to
`apply a second filter to a prediction value of the
`current block based on at least one of the intra
`prediction mode of the current block and the size of
`the current block, and applies the second filter to the
`prediction value of the current block if, as a result
`of the determination, the second filter is determined
`to be applied.
`Id. at 12:30–53.
`
`Claims 1 and 3 are identical, except that claim 1 in its preamble
`recites “A video decoding apparatus,” and claim 3 in its preamble
`recites “A video encoding apparatus.” Id. at 12:2, 12:30.
`
`E.
`
`Evidence Relied on by Petitioner
`Petitioner relies on the following evidence:1
`References
`Date
`Moon
`Published Sep. 15, 2005
`
`U.S. Pub. App. US
`2005/0201633 A1
`
`Teng
`
`U.S. Pat. 8,681,867 B2
`
`Issued Mar. 25, 2014,
`filed Feb. 8, 2006
`
`Exhibit
`Ex. 1004
`
`Ex. 1005
`
`Wilkins
`
`U.S. Pat. 8,326,075 B2
`
`Issued Dec. 4, 2012, filed
`Dec. 5, 2008
`
`Ex. 1006
`
`
`
`1 The ’448 patent issued from Application 14/825,825, filed Aug. 13, 2015,
`which is a continuation of Application 13/640,014, filed as
`PCT/KR2011/002514, on April 11, 2011, now Patent 9,549,204. Ex. 1001
`at codes (21), (22), (63). The ’488 patent also claims foreign priority to KR
`10-2010-0032778, filed Apr. 9, 2010, KR 10-2011-0026079, filed Mar. 23,
`2011, and KR 10-2011-0032766, filed Apr. 8, 2011. Id. at code (30).
`
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`IPR2021-00827
`Patent 9,781,448 B2
`Petitioner also relies on the Declaration of Immanuel Freedman, Ph.D.
`(Ex. 1003).
`
`F.
`
`Asserted Grounds of Unpatentability
`Petitioner asserts that the challenged claims are unpatentable on the
`following grounds:
`
`Claims Challenged
`
`35 U.S.C. §2
`
`Basis
`
`1, 3
`
`1, 3
`
`103
`
`103
`
`Moon, Wilkins, Teng
`
`Moon, Teng
`
`A.
`
`II. ANALYSIS
`Level of Ordinary Skill
`Petitioner asserts that one of ordinary skill in the art as of April 9,
`2010, would have had “(1) at least an undergraduate degree in electrical
`engineering or computer engineering or a closely related scientific field,
`such as physics or computer science, or similar advanced post-graduate
`education in this area; (2) a working knowledge of video coding techniques;
`and (3) at least two years of experience with video processing.” Pet. 10
`(citing Ex. 1003 ¶¶ 31–32). Patent Owner has not made its own assertion of
`the level of ordinary skill. Nor has Patent Owner expressed disagreement
`with Petitioner’s articulation.
`
`
`2 The Leahy-Smith America Invents Act (“AIA”), Pub. L. No. 112–29, 125
`Stat. 284, 287–88 (2011), revised 35 U.S.C. §§ 102 and 103 effective
`March 16, 2013. Because the effective filing date of the ’488 patent is prior
`to March 16, 2013 (Ex. 1001, codes (22), (63)), we refer to the pre-AIA
`versions of §§ 102, 103.
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`Patent 9,781,448 B2
`Petitioner’s use of the qualifier “at least” renders the articulation
`vague and potentially overlapping with the level of skill of an expert. Also,
`“similar advanced post-graduate education” is not consistent with an
`undergraduate degree first introduced in Petitioner’s articulation.
`On this record, we adopt Petitioner’s articulation of the level of
`ordinary skill, but delete the qualifier “at least” for the level of education and
`for the amount of experience, to keep the level from being vague and
`overbroad and extending into the level of an expert, and delete “or similar
`advanced post-graduate education in this area” also to keep the level from
`potentially extending into the realm of an expert. What remains appears
`consistent with what is reflected by the content of the applied prior art
`references. Cf. Okajima v. Bourdeau, 261 F.3d 1350, 1354–55 (Fed. Cir.
`2001) (the applied prior art may reflect an appropriate level of skill).
`For purposes of this Decision, we find the level of ordinary skill in the
`art corresponds to that of one who had, on or about April 9, 2010, the level
`of: (1) an undergraduate degree in electrical engineering or computer
`engineering or a closely related scientific field, such as physics or computer
`science; (2) a working knowledge of video coding techniques; and (3) two
`years of experience with video processing.
`
`B.
`
`Claim Construction
`We use the same claim construction standard that would be used to
`construe the claim in a civil action under 35 U.S.C. § 282(b), including
`construing the claim in accordance with the ordinary and customary
`meaning of such claim as understood by one of ordinary skill in the art and
`the prosecution history pertaining to the patent. 37 C.F.R. § 42.100(b)
`(2020). The Petition here was filed on April 22, 2021. Paper 1. We apply
`
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`Patent 9,781,448 B2
`the claim construction standard from Phillips v. AWH Corp., 415 F.3d 1303
`(Fed. Cir. 2005) (en banc) (“the Phillips standard”).
`Claim terms are generally given their ordinary and customary
`meaning as would be understood by one with ordinary skill in the art in the
`context of the specification, the prosecution history, other claims, and even
`extrinsic evidence including expert and inventor testimony, dictionaries, and
`learned treatises, although extrinsic evidence is less significant than the
`intrinsic record. Phillips, 415 F.3d at 1312–17. Usually, the specification is
`dispositive, and it is the single best guide to the meaning of a disputed term.
`Id. at 1315.
`The specification may reveal a special definition given to a claim term
`by the patentee, or the specification or prosecution history may reveal an
`intentional disclaimer or disavowal of claim scope by the inventor. Id. at
`1316. If an inventor acts as his or her own lexicographer, the definition
`must be set forth in the specification with reasonable clarity, deliberateness,
`and precision. Renishaw PLC v. Marposs Societa’ per Azioni, 158 F.3d
`1243, 1249 (Fed. Cir. 1998). The disavowal, if any, can be effectuated by
`language in the specification or the prosecution history. Poly-America, L.P.
`v. API Indus., Inc., 839 F.3d 1131, 1136 (Fed. Cir. 2016).
`Only those claim terms that are in controversy need to be construed,
`and only to the extent necessary to resolve the controversy. Nidec Motor
`Corp. v. Zhongshan Broad Ocean Motor Co., 868 F.3d 1013, 1017 (Fed.
`Cir. 2017); Wellman, Inc. v. Eastman Chem. Co., 642 F.3d 1355, 1361 (Fed.
`Cir. 2011); Vivid Techs., Inc. v. Am. Sci. & Eng’g, Inc., 200 F.3d 795, 803
`(Fed. Cir. 1999).
`Petitioner has not proposed a construction for any claim term.
`However, in applying the prior art to the claims, Petitioner reads the claim
`
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`Patent 9,781,448 B2
`term “prediction value,” appearing in both claims 1 and 3, onto original
`values which have been reconstructed or restored based in part on values
`which have been earlier predicted, and original values, of course, are not
`themselves predicted. Patent Owner proposes an express construction for
`“prediction value.” Prelim. Resp. 8–16.
`A petition is required to set forth “[h]ow the challenged claim is to be
`construed.” 37 C.F.R. § 42.104(b)(3). Although that does not mean
`Petitioner must expressly construe each claim term, in this case Petitioner
`should have provided and explained its own construction of “prediction
`value,” a critical term in the claims.
`“prediction value”
`Patent Owner asserts that “prediction value” should be construed to
`mean “a value generated in an intra-prediction process for determination of a
`prediction block.” Prelim. Resp. 8. We agree.
`Claims 1 and 3 each recite:
`when the intra-prediction for the current block is
`performed, the processor determines whether to apply a second
`filter to a prediction value of the current block . . . , and applies
`the second filter to the prediction value of the current block if,
`as a result of the determination, the second filter is determined
`to be applied
`Ex. 1001, 12:18–25, 12:46–53 (emphasis added). The language links
`“prediction value” to intra-prediction such that it is a predicted value
`generated inside an intra-prediction process performed on a current block to
`determine a prediction block for the current block.
`The Specification of the ’448 patent supports this reading by
`conveying that intra-prediction concludes with the final determination and
`outputting of prediction block “P” from the box in Figure 1 that is labeled
`
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`IPR2021-00827
`Patent 9,781,448 B2
`“Intra-prediction.” Ex. 1001, 5:6–6:4, Fig. 1. For clarity, we reproduce
`Figure 1 below, with color annotation (“Intra-prediction” box circled in red,
`and prediction block “P” colored in red with textual annotation):
`
`
`The above Figure is a color annotated version of Figure 1 of the ’448 patent,
`which is a block diagram of a described encoder. Ex. 1001, 3:30–31.
`We agree with Patent Owner that “prediction value” means “a value
`generated in an intra-prediction process for determination of a prediction
`block.” Values generated in post intra-prediction stages which use the
`prediction block as partial input, such as (1) residual or difference block Dn
`calculated by subtracting prediction block P from the current block (Ex.
`1001, 4:33–34), or (2) reconstruction block uF′n calculated by adding
`prediction block P back to restored difference macroblock D′n (Ex. 1001,
`4:43–54), are not and cannot be prediction values. Residual or difference
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`Patent 9,781,448 B2
`block Dn and reconstruction block uF′n are generated outside of the intra-
`prediction process while using completely determined prediction block P as
`partial input. Indeed, reconstruction block uF′n is a restored approximation
`of the original block Fn as it existed prior to the performance of any intra
`prediction. Ex. 1001, 4:52–55; see also Ex. 1009, 186.3
`The Specification further supports this construction by not referring to
`anything subsequent to the production of prediction block P as a part of intra
`prediction. We agree with Patent Owner that the ’448 patent makes clear
`that intra prediction for a current block does not extend beyond computation
`of the final prediction block P. Prelim. Resp. 12–13. The ’448 patent states:
`“If, as a result of the determination, the filter is determined to have been
`applied to the prediction value, the encoder applies the filter to the prediction
`value at step S205. Accordingly, the prediction of the current block is
`completed, . . . .” Ex. 1001, 9:13–17.
`For this decision, no other term requires an express construction.4
`
`C.
`
`Alleged Obviousness of
`Claims 1 and 3 over Moon, Wilkins, and Teng
`Law on Obviousness
`1.
`A claim is unpatentable under 35 U.S.C. § 103 if the differences
`between the claimed subject matter and the prior art are such that the subject
`matter, as a whole, would have been obvious to a person having ordinary
`skill in the art to which said subject matter pertains. See KSR Int’l Co. v.
`Teleflex Inc., 550 U.S. 398, 406 (2007). The question of obviousness is
`
`3 Iain E.G. Richardson, H.264 and MPEG-4 Video Compression, John Wiley
`& Sons Ltd. (2003).
`4 We need not determine whether the preamble of claims 1 and 3 is limiting
`because, as discussed below, Petitioner has not adequately accounted for the
`limitations in the body of claims 1 and 3.
`
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`IPR2021-00827
`Patent 9,781,448 B2
`resolved on the basis of underlying factual determinations, including (1) the
`scope and content of the prior art; (2) any differences between the claimed
`subject matter and the prior art; (3) the level of skill in the art; and (4) where
`in evidence, so-called secondary considerations, including commercial
`success, long-felt but unsolved needs, failure of others, and unexpected
`results (“the Graham factors”). Graham v. John Deere Co. of Kansas City,
`383 U.S. 1, 17–18 (1966).
`Overview of Moon
`2.
`Moon relates to encoding and decoding of motion picture data and a
`filter for removing a blocking effect. Ex. 1004 ¶ 3. Moon explains that
`because coding is performed in block units, a blocking effect arises where
`discontinuity occurs at boundaries between blocks. Id. ¶ 6. Moon states that
`a blocking effect is a type of image quality degradation, where discontinuity
`on block boundaries occurs regularly like laid tiles as compression rate
`increases. Id. ¶ 9. Moon describes that to remove such blocking effect,
`filters are used and filters are classified into loop filters and post filters. Id.
`Loop filters output a filtered frame which is then used as a reference frame
`for the next frame. Id. ¶ 10. According to Moon, “[p]ost filters are located
`on the rear portions of encoders and can be designed independently of
`decoders.” Id.
`Figure 1 of Moon shows a block diagram of an encoder and is
`reproduced below:
`
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`IPR2021-00827
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`
`
`Figure 1 illustrates an encoder including motion estimator unit 102, motion
`compensator 104, intra predictor 106, transformer 108, quantizer 110, re-
`arranger 112, entropy decoder 114, de-quantizer 116, inverse transformer
`118, filter 120, and frame memory 122. Id. ¶ 39. The input to filter 20 is a
`reconstructed or restored block uF′n – not any output of intra predictor 106.
`Id. ¶ 48. The filtered restored picture is then stored in frame memory 122
`“and is then used to perform an interprediction on a picture that follows the
`current picture.” Id.
`
`Moon also describes, regarding filter 120, selectively applying the
`filtering depending on the circumstance. Id. ¶¶ 56, 85–87. Moon describes
`that whether to apply filtering depends on a boundary strength (Bs
`parameter) of the block. Id. ¶¶ 85–87. Moon provides a table showing
`conditions that correspond to various Bs parameters:
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`
`
`Id. ¶ 85. Moon states that a “Bs parameter of 0 indicates that there is no
`need for filtering.” Id. ¶ 87.
`Overview of Teng
`3.
`Teng explains: “[W]hen a video frame is divided into video blocks
`for video coding, the edge of one coded video block may appear
`discontinuous with the adjacent edge of another coded video block. When
`this occurs, the decoded video frame may appear ‘blocky,’ which is highly
`undesirable.” Ex. 1005, 2:5–8. Teng further explains:
`In order to remove such “blockiness,” filtering can be
`performed on the block boundaries of the video blocks to
`“smooth” the transitions between adjacent video blocks.
`Deblocking filters generally refer to filters that are used to
`smooth the transitions between adjacent video blocks to reduce
`or eliminate blockiness artifacts.
`Ex. 1005, 2:11–16. Teng states that it provides for “selective deblock
`filtering.” Id. at 2:42. Teng further describes that deblock filtering may be
`selectively performed while a video block is being coded, after a video
`frame is predicted, or both. Id. at 2:16–21, 2:48–52. Teng, however, does
`not describe that post filtering is applied to obtain final output values of intra
`prediction. Figure 1 illustrates an exemplary video coding device of Teng
`and is reproduced below:
`
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`
`
`
`
`Figure 1 is a block diagram of Teng’s video coding device 10. Id. at
`5:35. Teng states: “Coding device 10 may comprise any of a wide variety
`of devices that can be used to encode or decode video sequences.” Id. at
`5:36–38. Teng further describes: “Examples of coding device 10 generally
`include any computer, such as a server, a workstation or any other desktop
`computing device, or a mobile computing device such as a laptop computer
`or a personal digital assistant (PDA).” Id. at 5:38–42.
`Teng describes that its techniques may be implemented in hardware,
`software, firmware, or any combination thereof. Id. at 14:10–11. Teng
`further describes: “The program code may be stored on memory in the form
`of computer readable instructions. In that case, a processor such as a DSP
`may execute instructions stored in memory in order to carry out one or more
`of the deblock filtering techniques.” Id. at 14:22–25.
`Overview of Wilkins
`4.
`Wilkins discloses a loop filter that removes or reduces blocking
`artifacts. Ex. 1006, 2:41–42. Loop filter 34 is shown in Figures 1 and 2. Id.
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`at 2:41–45, 4:13–14, Fig. 1, 2. The output of loop filter 34 is provided to
`intra/inter prediction stage 18 (Figure 1) and intra/inter prediction stage 23
`(Figure 2) for performing intra/inter prediction. Id. at Figs. 1, 2.
`Wilkins also discloses a post-loop filter. Id. at 4:14–17; Fig. 2
`(deblocking filter 33). Deblocking filter 33, however, is disposed
`subsequent to reconstruction stage 31. Id. at 4:10–17; Fig. 2. Wilkins states:
`“At the reconstruction stage 31, the prediction macroblock can be added to
`the derivative residual to create a reconstructed macroblock.” Id. at 4:10–
`13. Thus, it is not the prediction macroblock from intra/inter prediction
`stage 23 that is provided to deblocking filter 33, but a reconstructed
`macroblock from reconstruction stage 31. Id. at 4:10–17, Fig. 2. Figure 2 of
`Wilkins shows a video decompression system (id. at 2:22–23) and is
`reproduced below:
`
`
`
`Figure 2 shows decoder 21 which has a structure similar to the
`reconstruction path of encoder 14 of Figure 1 (not shown). Id. at 3:59–67.
`
`Further, Wilkins describes modifying the strength of a loop filter, e.g.,
`loop filter 34. Id. at 3:1–3. In that regard, Wilkins states: “A filter that is
`too strong may cause blurring and loss of detail. A filter that is too weak
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`may not adequately suppress discontinuities between adjacent blocks.” Id.
`at 3:3–6. Specifically, Wilkins discloses application of strength modifier 60
`to provide additional loop filter control, based in part on whether intra
`prediction of the current block is performed in “split mode” or non “split
`mode.”5 Id. at 2:27–31, Fig. 4, 5.
`Petitioner’s Combination of Moon, Teng, and Wilkins
`5.
`Petitioner asserts that the disclosures of Moon, Teng, and Wilkins all
`relate to both encoding and decoding. Id. at 21 (citing Ex. 1004 ¶ 3; Ex. 1005,
`6:10–13; Ex. 1006, 3:7–10, 3:59–63). Petitioner explains:
`The proposed combination relies on the video coding
`apparatus of Moon, modified by the addition of Wilkins’s
`additional filtering criterion and in-loop deblocking filter. In
`particular, in the proposed combination, Moon’s filtering criteria
`(as embodied in filtering decision Table 1) is augmented by the
`additional filtering criteria of Wilkins based on the size of the
`current block and used to selectively apply both the post-loop
`filter of Moon and the in-loop filter of Wilkins. The video coding
`apparatus would include a processor such as Teng’s processor to
`perform the filter decision. Teng’s processor is particularly
`appropriate for implementing the conditional filtering decision
`because Teng’s disclosed processor is programmed to determine
`whether to apply a deblocking filter (such as, in the proposed
`combination, based on the criteria of Moon and Wilkins).
`Pet. 20. Petitioner further explains: “As applied to the system of Moon,
`such a modification would result in an additional (conditional) filter being
`applied to the reconstructed block before it is used for the purpose of intra-
`prediction, as shown in the diagram below from Dr. Freedman’s Declaration.
`Freedman Decl. at ¶ 55.” Id. at 22. The referenced diagram illustrating
`what results from Petitioner’s proposed combination is reproduced below:
`
`
`5 Dr. Freedman testifies that a distinction based on split-mode or non-split
`mode equates to a distinction based on block size. Ex. 1003 ¶ 53.
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`
`The Figure is Petitioner’s depiction of the resulting structure based on its
`proposed combination of Moon, Teng, and Wilkins. Pet. 22–23.
`Apply a filter to a prediction value of the current block
`6.
`Both claims 1 and 3 recite a processor that “when the intra-prediction
`for the current block is performed, . . . determines whether to apply a second
`filter to a prediction value of the current block” and “applies the second filter
`to the prediction value of the current block if, as a result of the
`determination, the second filter is determined to be applied.” Ex. 1001,
`2:18–25, 2:46–53. In Section II.B., we have construed “prediction value” to
`mean “a value generated in an intra-prediction process for
`determination of a prediction block.”
`Petitioner identifies Moon’s filter 120, i.e., filter 120 in the proposed
`combination of Moon, Teng, and Wilkins in the immediate above-
`reproduced Figure, as the claimed second filter. Pet. 47–48. Moon’s filter
`120, however, does not filter any prediction value of the current block.
`Rather, what is filtered by Moon’s filter 120 is reconstructed or restored
`block uF′n. Ex. 1004, Fig. 1. In Petitioner’s proposed combination of Moon,
`Teng, and Wilkins, what is filtered by filter 120 is version of reconstructed
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`or restored block uF′n which has been filtered once through a loop filter
`added on the basis of Wilkins (shown in the immediate above-reproduced
`Figure in red dotted lines). Pet. 22–23. As explained above in our claim
`construction analysis in Section II.B., however, a reconstructed or restored
`block (filtered or not filtered) does not include prediction values for the
`current block. In Moon, uF′n is generated at a stage in the coding process
`subsequent to the generation and complete determination of prediction block
`P. Ex. 1004, Fig. 1. Indeed, Moon states: “The restored current picture is
`stored in the frame memory 122, and is then used to perform an inter-
`prediction on a picture that follows the current picture. If the restored
`picture passes through the filter 120, it becomes the original picture that
`additionally includes several encoding errors.” Id. ¶ 48 (emphasis added).
`Petitioner makes no explanation as to why reconstructed or restored
`block uF′n would include prediction values for the current block, such that
`filter 120 is applied to a “prediction value” of the current block. Petitioner
`has not made a sufficient showing for a processor that “when the intra-
`prediction for the current block is performed, . . . determines whether to
`apply a second filter to a prediction value of the current block” and “applies
`the second filter to the prediction value of the current block if, as a result of
`the determination, the second filter is determined to be applied.”
`Based on at least one of an intra prediction mode of the
`7.
`current block and size of the current block
`Both claims 1 and 3 recite “a processor to determine whether to apply
`a first filter to a reference pixel value of a current block based on at least
`one of an intra prediction mode of the current block and a size of the current
`block.” Ex. 1001, 12:3–6 (emphasis added). Both claims 1 and 3 also recite
`“the processor determines whether to apply a second filter to a prediction
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`value of the current block based on at least one of the intra prediction mode
`of the current block and the size of the current block.” Id. at 12:19–22
`(emphasis added).
`For reasons discussed below, Petitioner has not made a sufficient
`showing for either condition on which application of the first and second
`filter is based, i.e., (1) an intra prediction mode of the current block, and
`(2) a size of the current block.
`based on an intra prediction mode of the current block
`a)
`The ’448 patent explains that there are nine different intra prediction
`modes for intra predicting a 4x4 block, and four intra prediction modes for
`intra predicting a 16x16 macroblock. Id. at 5:7–19. For example, the nine
`different modes for intra predicting a 4x4 block are illustrated in Figure 4,
`reproduced below:
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`Figure 4 shows nine intra prediction modes for a 4x4 block. Id. at 3:36–37,
`5:61–6:4.
`
`For the condition that application of